A law enforcement official says the gunman who fled after killing a police officer on campus is believed to be dead. The law enforcement official had knowledge of the case and spoke on condition of anonymity. After the officer was shot Thursday, authorities found a second body in a campus parking lot. It was not immediately clear if that second body was that of the gunman. The shooting triggered a lockdown on the sprawling campus that in 2007 was the scene of the deadliest mass shooting in U.S. history. School officials said earlier in the day that the officer was shot during a routine traffic stop. The officer has not yet been identified.